by Sol Jacobs, Tadiran Batteries Battery makers have devised chemistries that put a lot of energy in a tiny volume. Generally speaking, every penny counts when it comes to designing devices for a mass consumer market. That’s one reason smartphones use relatively inexpensive, rechargeable lithium polymer batteries for power. Constructed from a thin, flexible material, […]
Power Electronics Handbook
Choking off EMI/RFI in off-line switchers
by Jim Earley, President, Premier Magnetics Electromagnetic interference (EMI) and radio frequency interference (RFI) are natural byproducts of switching power supplies. Much of this noise arises as a direct result of the large voltage swings caused by short-duration charging and discharging in the power supply circuitry. Common mode noise, which is generated through the power […]
Cool calculations
by Steve Griffiths, Manager of Technical Sales and Marketing, Ametek, Dynamic Fluid Solutions Business Unit It pays to do a back-of-the-envelope thermal analysis before cranking up a CFD program for power electronics. Power electronics can generate a lot of heat, so much so that many modern power supplies incorporate fans or blowers to keep temperatures […]
Working with Wirewounds
by Kory Schroeder, Director of Product Marketing and Engineering, Stackpole Electronics Inc. For high currents, axial-leaded wirewound resistors are often good candidates because they can handle up to 10 W and double as fuses. When a task calls for dissipating kilowatts of power over an extended period, wirewound resistors are often a logical choice. These […]
How to evaluate cutting-edge power semiconductors
by Ryo Takeda and Alan Wadsworth, Keysight Technologies Investments in power semiconductor devices continue to grow. Performance and reliability also improve each year through the employment of new structures and new wide bandwidth materials such as SiC and GaN. Particularly with respect to these new power devices, it is important to evaluate operating properties. Sometimes […]
Selecting power supply connector pins
by David Norton, TDK-Lambda Americas Designers can avoid reliability problems by acquainting themselves with the way connector pin materials stand up to repeated use and corrosion. Examine the input and output connectors on most open-frame power supplies and you’ll likely find parts from a supplier like Molex or JST. These connectors are inexpensive, readily available, […]